Idk you just got to come out and do it. Their is snow reading and terrain reading. A lot of stuff you see is "prime" and folks generally know (have ridden) or have really scoped the line first and what you see is a really good day in terms of pow and only a small amount of film. Idk but for 30 sec of good edit it might have taken all day or waiting for weeks for the right time to hit it. Some of the stuff I love to hit when its deep, dry and fluffy...I'm lucky to hit it for 3 or 4 runs in an entire season.
Here's a recent re-edit compilation from last season that the kids did.